Preview Tool

Cisco Bug: CSCul63295 - Glare condition in EX90-CUBE call results in extra mlines. Call drops.

Last Modified

Nov 14, 2015

Products (7)

  • Cisco Unified Communications Manager (CallManager)
  • Cisco Intercompany Media Engine
  • Cisco Unity Connection Version 9.1
  • Cisco Business Edition 5000 Version 9.1
  • Cisco Unified Communications Manager Version 9.1
  • Cisco Business Edition 6000 Version 9.1
  • Cisco Unified Communications Manager Session Management Edition

Known Affected Releases


Description (partial)

Glare condition in EX90 to CUBE call results in additional mlines being sent resulting in an RFC violation and call drop.

Call flow:


SIP trunk to CUBE is set for delayed offer.  Call from EX90 goes across CUBE to another VCS system and lands on IVR.  Call should be audio only at this point.

Both sides send re-INVITE and CUCM ends up adding additional mlines in the answer to CUBE resulting in the call to drop.

The re-INVITE that comes back from the CUBE is:

o=TCLSM 74539634924501 74539634924502 IN IP4 
c=IN IP4 
t=0 0 
m=audio 17410 RTP/AVP 0 101 
a=rtpmap:0 PCMU/8000 
a=rtpmap:101 telephone-event/8000

a=fmtp:101 0-15 

and the answer to that in the 200 OK is: 

o=CiscoSystemsCCM-SIP 194301 3 IN IP4 
s=SIP Call 
c=IN IP4 
t=0 0 
m=audio 2346 RTP/AVP 0 101 
a=rtpmap:0 PCMU/8000 
a=rtpmap:101 telephone-event/8000 
a=fmtp:101 0-15 
m=audio 0 RTP/AVP 0 
m=audio 0 RTP/AVP 0 
m=audio 0 RTP/AVP 0

CUBE responds with the following:

SBC/BM: MSG-4C02-0292-0DFA84-0699 at 22:44:29, 29 October 2013 ( 1525074327 ms): 
SBC/BM: An SDP answer either contains a different number of media lines from 
SBC/BM: the media description in the corresponding SDP offer, or it contains a 
SBC/BM: media description with no formats in common with the formats in the 
SBC/BM: corresponding SDP offer, or the answerer has enabled a disabled stream. 
SBC/BM: This is illegal SDP and SBC releases the call. 
SBC/BM: Offered SDP : v=0

SIP trunk to CUBE is set for Delayed Offer.
Bug details contain sensitive information and therefore require a account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.